Windows 10 won't compile

[Stephen Moss]

I wonder what happens if you restore a FULL backup?

If your PC has one of those restore to factory condition options that copies the OS across from a hidden partition then that should restore S mode if that was how it was shipped, the downside of doing that is that you then have to re-install all your other software. But if you need to use software not available from the Microsoft store then what would be the point of restoring S mode.

For years Microsoft have been removing (or deeply burying) the users ability to do even simple things like changing the default Windows background and foreground colours to black text on a Silver background or White text on a Black background for those who find a White background a strain on the eyes. For a while the only way was to load an old saved Theme set up that way, until someone at Microsoft eventually got the message and created a Dark mode.

I think S mode is an extension of this, I think they started down that route to limit the ways people who don't know what they are doing could really screw things up. There is some logic to that in that in should ensures a more error free operation for the end user and reduce the amount of time spent resolving stupid problems, which can then be better spent on resolving more deeper problems. Thus trying to limit the home user to software that is known to be 100% compatible with their OS and will not make changes to anything it shouldn't.

Whereas when people install any one of a thousand other programs then only way they may be able to solve the issue may be to purchase and install the software, and so essentially the warning about switching out of S mode is meant to deter you from doing so unless you are reasonably confident you can solve any arising issues yourself or have an IT expert available to do it for you.

[keytapper]

It's just what the Linux distros doing. No programs are allowed to install when the origins are unknown. So every software is signed and there's that check. The only advantages are that most of the programs are FOSS. Even android uses the same condition,  but it leaves the option to disable the verification, with the option to go back.